


the other third of our heart

by Lauren (notalwaysweak)



Category: The Big Bang Theory (TV)
Genre: Alternate Universe - Triadverse, F/F, F/M, M/M, Multi
Language: English
Status: Completed
Published: 2013-12-14
Updated: 2013-12-14
Packaged: 2018-01-04 11:57:31
Rating: Mature
Warnings: No Archive Warnings Apply
Chapters: 8
Words: 3,358
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/1080730
Author URL: https://archiveofourown.org/users/notalwaysweak/pseuds/Lauren
Summary: <blockquote class="userstuff">
              <p>Sheldon and Penny search for the third vertex of their triad. Not all relationships listed because frankly there were too many. Written for jen4850 for Saturnalia 2013.</p>
            </blockquote>





	1. and now, when it’s leonard, and they’re realizing it always has been

**Author's Note:**

  * For [JenniferEsther](https://archiveofourown.org/users/JenniferEsther/gifts).



> TBBT characters do not belong to me and I am making no money off this work of fan fiction.
> 
> Betaed by Jen (jazzfic), for which I am eminently grateful, as always.
> 
> * * *

Sheldon looks less stunned than Penny would have predicted as Leonard lets go of Sheldon’s shoulders and drops back down from his tiptoes. Leonard looks determined and defiant and also terrified. The apartment is silent save for the distant popping of fireworks.

Sheldon licks his lips, possibly chasing the taste of Leonard’s mouth. “Leonard. What was that?”

Penny looks from one of them to the other. In this moment, in their living room, she can believe that this will turn out absolutely perfectly, or that their lives could go completely to shit.

“You know what it was,” Leonard says quietly. “The real question is, do you accept?”

The silence that follows lasts for an eternal five seconds. Sheldon looks at Penny. Penny tries to look hopeful while simultaneously not looking too hopeful, which is hard and makes her think she probably just looks confused.

“I--” Sheldon clears his throat. “I--”


	2. back then, when it was probably going to be amy

“I bought you a nose clip to try,” Amy says, offering the little box to Penny. “It should assist with your nocturnal rowdiness.”

“Thanks, sweetie,” Penny says, tucking the box into her apron pocket and resolving to at least attempt to remember to retrieve it before she tosses the apron into the laundry basket out back. Amy looks a little disappointed. “I’ve got your margarita and Sheldon’s virgin diet Cuba Libre.”

“I hope it’s _really_ virgin this time.” Sheldon glowers a little.

“As virgin as you were our first time, sweetie,” Penny assures him. Then she flees the scene in the general direction of the bar before he can come up with a retort. Amy’s openly snickering. The next table over look amused as well, although she hadn’t intended her comment to be for the entertainment of the whole restaurant.

When she gets back to the bar Bernadette’s waiting for her, perched up on one of the stools, feet dangling. Howard and Raj are at their usual table, holding hands across it and just doing the gazing thing again.

“I’d say it’s the blush of new love,” Bernadette says, catching the direction of Penny’s glance, “but it’s been almost a year now and they keep doing it.”

“So long as you don’t get left out.”

“Oh, I don’t. Last night we--”

“Don’t need details, just confirmation that everything’s okay.”

Bernadette gives her a double thumbs-up, which could qualify as TMI on its own considering the dainty leer that accompanies it. Penny goes behind the bar and starts mixing their drinks; the first round of the night is always the same for the Rostenrappawitz triad.

“What about you three? Is everything okay?”

“Well, apart from the fact that I got called to work on date night and Amy’s idea of a gift is this thing to stop me snoring, not too bad. She’s a little clingy sometimes, but since we trained her to do it to me more than to Sheldon, it’s less of a problem.”

“An anti-snoring device?” Bernadette has apparently seized on the part of the conversation most relevant to her interests. “I could use one of those for Raj. Can I see?”

Penny fishes the box out of her apron pocket and pushes it across the bar. “Go nuts.” She’s barely picked the cocktail shaker back up when Bernadette gasps, and Penny’s stomach just about drops out of her shoes when Bernadette turns the box around to show her.

“I don’t think this is going to stop you snoring, but it might start you screaming,” Bernadette says.

It’s _not_ a nose clip. And now she knows why Amy looked disappointed when she didn’t open it at the table.

“Oh, my God.” Penny reaches out and snatches the ring out of Bernadette’s hand and shoves the box back into her pocket. “Don’t tell her you saw it, okay?”

“It sounds like everything’s not all right,” Bernadette says tentatively.

“I just don’t know if I can commit with her.” The words come out all at once. “I do like her a whole lot, and so does Sheldon. But...”

“But what?”

Penny looks across the restaurant. Leonard has joined Sheldon and Amy at their table, and the three of them are laughing at something. Sheldon has his arm draped over the back of Amy’s chair in a fairly perfunctory way. “She’s just not one of our vertexes,” she admits.

“Vertices.”

“What _ever_.” She gestures to the table. “But she could be one of Leonard’s, maybe. Do you think she’d get along with Priya?”

“I think Priya would eat her alive and pick her teeth with the bones,” Bernadette says flatly.

“You may have a point.”

* * *

Penny keeps looking at the two tables all night.

Bernadette, Howard, and Raj: established for almost a year now and there’s no telling really which partnership is the base and which are the sides. They’re the truest equilateral she knows. She’s pretty sure that even before Raj was confirmed as their third, even before it was Bernadette and Howard, that it was Howard and Raj, and so far her theory has not been disproven.

And then Sheldon, Amy, and Leonard: she thought she and Sheldon were the base, but a tiny green seed flowers in her heart when she sees how the three of them talk and laugh together.

But Sheldon comes home with her, and Amy goes to her own place, and Leonard goes on to a couples’ night that Stuart’s holding at the comic book store for geeks seeking thirds, and Penny manages to forget all about both her jealousy and about the promise ring in the little box by the time Sheldon’s gotten her into the bedroom, intent on proving just how far he’s come since their first night together.

* * *

 

The next day, she talks to Sheldon about the ring, and they get Amy on Skype at breakfast time. The conversation is both shorter and politer than Penny expected.

“At this stage it’s all or nothing,” Amy says.

And: “I’ll take the ring back next time I see you, or you can send it with Sheldon, since I’m at the Caltech labs today.”

That’s the end of it. Penny packs up Amy’s things that have found their way to Penny and Sheldon’s apartment, and realizes when there are so few of them -- a little clothing, anti-dandruff shampoo, some books -- that this has always been the way that it was going to turn out.

It’s not that it doesn’t hurt. It’s just that it hurts less than she’d expected.


	3. in the beginning, when one became two

Penny slides down the wall into a puddle of groceries, narrowly avoiding sitting in the ice cream, and covers her face with her hands, because all the small things just piled on up and then fell over on her with a resounding crash and she’s flat out of cope.

The apartment door across from her opens. She hears the sound of footsteps, the rustle of bags. Of _course_. Sheldon just can’t stand a mess, can he? Not even long enough to give her time to cry it out.

He comes and goes a couple of times. She hears the fridge open and close and things clunking on the bench. She still doesn’t move and keeps her hands over her face. The world seems simpler when it’s reduced to the darkness behind her eyelids.

“Penny.”

“ _What_.”

“Penny, you have to get up.”

“No.”

His knees pop when he crouches down beside her; his breath stirs the hair beside her ear and he slips one arm under her bent knees, the other around her shoulders. She’d always thought that he had the upper body strength of a two-year-old, but he manages to lift her up, carry her into his apartment, and deposit her on the couch with minimal effort.

“Shel _don_!” She only notices when he lets her go that she’s thrown her own arms around him, and in fact is holding on tightly enough that he can’t straighten up.

“I was going to make you tea, but I can’t because you have a death grip on my neck,” Sheldon informs her.

“Sorry.” Penny lets go and Sheldon overbalances, rebounding off the coffee table before falling to his knees beside the couch, catching himself with one hand against the end of the couch before he can land on top of her.

“Ow.”

“Oh my God, are you all right?” Suddenly her own ridiculous plight seems both less serious and less ridiculous in the face of Sheldon doing a credible impersonation of a fainting stick insect.

“I may just stay here for a moment while I ascertain whether or not my patellae are broken.”

“I’m sure they’re fine, sweetie.” He means his knees, right? She doesn’t think she heard anything snap. She pats his hand reassuringly, and he turns his hand over and twines his fingers through hers.

“While I’m down here, there’s something I was meaning to ask you.”

“Uh... sweetie, you need to be careful saying that when you’re on your knees.”

Sheldon gives her a quizzical look. “I just wondered if you’d mind helping me conduct an experiment.”

“You’re not making it any better.” Although she is relieved at the lack of a ring appearing. They get on extraordinarily well, but it’s not like they’ve been dating or anything.

“I’ve been growing aware recently of the societal pressures surrounding relationships and--”

Penny kisses him. Hauls his head down to hers, seals her lips to his, and dares a flick of her tongue over his lower lip when he doesn’t immediately flail and pull away. He opens to her and she to him and the feeling of his long fingers cradling her cheek as the kiss slips from passionate to sweet and back again is what she realizes she’s been waiting for.

Because considering their intimate knowledge of each other's routines and likes and dislikes, it  _is_ kind of like they've been dating.

“Long story short, was that what you were going to ask me about?” she asks a few delightful minutes later.

“Yes, actually.” And this time he initiates the kiss.

It’s so _refreshing_ , the times when she gets to cut through his bullshit and straight to the heart of the matter. 


	4. before amy, when they were still figuring themselves out one third at a time

“I can’t imagine that a relationship based solely upon sex is going to work out in the long term,” Sheldon says, his voice remarkably steady under the circumstances.

“We don’t have to make it long term. Just, you know, maybe fairly frequent short term.” Penny is proud of herself for making the words make that much sense. She’s pretty sure her intention was clear, anyway.

“Can you stop dissecting what’s going on here and just snuggle?” Wil asks, nuzzling the side of Penny’s neck. “I’m not finished with _you_ , Sheldon,” he adds as Sheldon tries to move. At least that’s what Penny thinks is going on; she’s spooned up against Wil’s side and her eyes are shut and she’s still working on this whole thinking thing, let alone figuring out what Sheldon’s doing based on the movement of his body on the bed.

She opens her eyes and curls her upper body around to rest her head on Wil’s chest. He has one arm around her, playing with her hair; his other hand is doing obscene things between Sheldon’s legs. Sheldon’s face makes it look like he doesn’t know whether he’s disconcerted about this interplay between himself and his former mortal enemy, or about to come his brains out.

It turns out to be the latter.

* * *

Stuart works out surprisingly well for exactly two and a half dates. Turns out that the time Sheldon thought he was being deliberately provocative? He totally was -- just not in the way that Sheldon thought.

And then Sheldon has a stupid loud argument with him in the movie theater about _Raisinets_ of all things, and she has to drive them both home in silence, feeling uncomfortably like their chauffeur.

When she pulls over to let Stuart out he leans over from the passenger seat and kisses her goodnight with slow regret, and she ignores Sheldon’s disgruntled sigh for just a second to slip her fingers through Stuart’s curls and kiss him back.

* * *

Leslie. Leslie was a bad idea when she was with Leonard, and she was a bad idea when she was playing around with Howard, but holy hell does the hatred between her and Sheldon ever spark a fire in the bedroom.

And the living room, and the shower, and Leslie’s lab, and Sheldon’s office.

It actually sort of almost works for nearly a month, but then they get to the talking about feelings and stuff side of things that they completely skipped on their way to the bedroom (living room, shower, etc. etc. etc.), and that’s where it all falls apart.

After that, Penny and Sheldon make each other a promise: feelings first, sex afterwards.

(This works fine up until Wil appears on the scene. _Wheaton_.)


	5. during all this: in which leonard has dating issues

Leonard and Leslie doesn’t work.

Leonard and Joy doesn’t work on, like, a subatomic level.

Leonard and Stephanie works for a little while, and when it fizzles Penny is secretly disappointed; she thinks he’d do well with a hot doctor. ( _She_ is, after all.)

Leonard and Priya -- well.

_Before_ Leonard and Priya there’s the New Year’s party where Sheldon and Penny have been together for two years, Amy’s been on trial for a couple of months, and three people kissing at once has always been a tricky prospect. Tradition dictates that one of the triad kisses a member of another triad to signify their close ties, but Bernadette, Howard, and Raj have _all_ mysteriously disappeared.

So when the clock strikes twelve and the ball drops and the countdown ends, Penny glances over to see Sheldon planting one on Amy, and then finds Leonard’s hand slipping into hers, and.

It’s a nice kiss. More than nice, in fact. He doesn’t try to lick her face off like Zack used to (and thank God for small mercies that _he’s_ not on the scene any more), nor does he seem at all nervous about it (which she’s quite successfully trained Sheldon out of -- more small mercies). She’s uncomfortably reminded of her first kiss with Sheldon, actually, of the progression from _is this okay?_ to _mmmm, this is working really well_ to _why did I wait so long to do this?_

That thought is what makes her pull back, more abruptly than she’d intended.

“Sorry,” says Leonard, looking anything but repentant.

Then Sheldon’s there, either unaware of or merely ignoring what just happened, and he leans in to kiss Leonard on the cheek. He grazes the very corner of Leonard’s mouth instead and Penny’s super aware of the way that Leonard’s fingers go up to touch the spot before Sheldon pulls her in and she closes her eyes.

* * *

Priya comes onto the scene for what Penny thinks is for good two months later, just in time to give her blessing to her brother at last becoming the third part of the Rostenrappawitz triad. In fact, she’s the one who helps them figure out that yes, that name flows a little better than Koothrawolowski, or Howberaj, or in fact any of the other combinations they’ve come up with. (Howjeshette is Penny’s personal favorite, but nobody else but her likes it.)

The tradition is to at least try to come up with a portmanteau for legal purposes but honestly, Penny’s never met a triad or even a couple who actually use them, the reason being that quite frankly they sound fucking ridiculous. Not to mention that every single one anyone has come up with for her and Sheldon and Amy starts with _Shamy_ , which is uncomfortably close to _shame_.

But it’s a funny enough game, and it helps solidify Priya’s place in the grand scheme of things, and things seem to cruise along there between her and Leonard for a good while.

Then things start to fall apart. Which is Alanis-ironic because it’s fall, and the brown leaves are falling, and somehow in the middle of it all Sheldon Cooper is Penny’s evergreen constant, which was not what she’d expected when she first moved into 4B.

The Rostenrappawitz triad -- who have all latched onto the name like a trio of molluscs with a penchant for inanity -- are fine, but first there’s Amy’s awkward not-quite-proposal, and then a month later Leonard and Priya break up, unable to cope with the distance between Pasadena and New Delhi, which coincides with the abrupt tumble of Wil into Sheldon and Penny’s sphere of existence (and bed).

Apparently there’s something in the water at Stuart’s Halloween party, because not only is that where Sheldon and Penny take Wil home from, it’s also where Leonard does something ill-advised with Stuart and Stuart’s new girlfriend Alice. Granted, it _looks_ like fun -- so Penny thinks as she slams the door to the TARDIS photo booth and then, for good measure, the door into the back room as well -- but surely that can’t be a good way to treat such a long scarf.

Leonard comes out twenty minutes later, flushed and giggling, and Penny takes a moment to give him an affectionate peck on the cheek, highly aware of Sheldon and Wil waiting for her by the door.

“I’m glad you’re happy,” she says.

Leonard squeezes her hands. “I’m not,” he says, and she hears the slur of alcohol in his voice. “But I’m doing a good job of pretending, so who cares?”

Penny opens her mouth, trying to think of something to say, but the words just aren’t coming, least of all when she turns to see Wil doing obscene things to the side of Sheldon’s neck with his mouth.

(She thinks the word _obscene_ about Wil a lot, and doesn’t know why.)

“I’ll be fine,” Leonard reassures her. “You go on, enjoy the party.”

Penny has no intention of staying at the party, but she nods and smiles and waits until he’s disappeared into the throng before making a mad dash for the door.


	6. earlier this afternoon (a little before now)

“We _could_ go to Wheaton’s party,” Sheldon says, “but that could be socially awkward on a lot of levels.”

“I’m just glad you realize that,” Penny says.

The Rostenrappawitzes have gone to Vegas, ostensibly to drink and gamble, but Penny suspects wedding bells ringing in their future and is glad. She’d like for them to have a big ceremony here at home so that she can dress up and drink champagne, but she knows that the spur of the moment thing will appeal to all of them and that the kitschiness of it all will appeal to Raj in particular.

“You guys could just stay home and I’ll go see what’s in my liquor cabinet,” Leonard offers.

“I guess it would be nice to have a quiet New Year’s for once. Leonard, weren’t you planning on going to Stuart’s mixer?”

Leonard goes ever so slightly pink, which is now his standard reaction to any mention of or proximity to Stuart, and shrugs. “Been there, done that,” is all he says.

“Got the t-shirt,” Penny adds. “And the 35% store discount.”

“A boy has to have his perks,” Leonard says primly, ducking across the hall on a wave of laughter.


	7. almost now

The ball’s dropping in Times Square and all three of them are on their feet, wine glasses raised.

Penny puts down her glass on the coffee table as the countdown reaches zero and the fireworks start for real outside. There have been several false starts. She turns to Sheldon, but Leonard interposes himself between them, stretches up on his tiptoes, and kisses Sheldon hard on his surprised mouth. His hands brace on Sheldon’s shoulders for support and Sheldon’s hands creep hesitantly around his waist.

Sheldon looks less stunned than Penny would have predicted as Leonard lets go of Sheldon’s shoulders and drops back down from his tiptoes. Leonard looks determined and defiant and also terrified. 

And--


	8. now

“Penny?” Sheldon asks.

Penny just reaches out and takes Leonard’s hand in her left and Sheldon’s hand in her right. Sheldon looks at her, looks at Leonard, and then closes the circle.

Three people kissing at once has always been a tricky prospect, but somehow, this time, they make it work.


End file.
